Various methods have been proposed in which a parallax image corresponding to an input two-dimensional image is generated to enable three-dimensional display. The parallax image is generated by obtaining a parallax vector per pixel from an input image and the depth information thereof, and assigning the pixel values of the pixels of the input image to the positions indicated by the resultant parallax vectors. During generation of the parallax image, a blank area (shade forming area), to which no pixel values are assigned, may well occur. JP-A 2004-295859 (KOKAI) discloses a three-dimensional image generating apparatus, in which pixel values assigned to the pixels of the blank area are generated for interpolation based on pixel values corresponding to the end portions of the image components adjacent to the blank area. Further, a non-patent document—Antonio Criminasi, Patrick Perez and Kentaro Toyama, “Region Filling and Object Removal by Exemplar-Based Image Inpainting,” IEEE Trans. Image Processing, Vol. 13, No. 9, September 2004—discloses an image inpainting technique used for, for example, image repairing. In this technique, the pixel values of a blank area in an image are interpolated using pixels in the boundary between the blank area and a non-blank area adjacent thereto. In this pixel interpolation, interpolation may be performed on the blank area, based on the pixel values of an area indicating, for example, an object near a photographer, even when the blank area is a background.
In the above-mentioned conventional pixel interpolation, unnatural images may well be generated as a result of interpolation of the pixel values of a blank area based on the pixel values of a foreground.